Unevenly and overly worn tread on tires may reduce tire life and increase fuel consumption, besides being a hazard to drivers. Further, uneven wear on tire tread may waste tires and accelerate scrap growth creating stockpiles of tires posing a threat to public health, safety and the environment.
Many factors may cause such wear on tire tread including failure to rotate tires, underinflation of tires, alignment issues, and/or the like. It is estimated that tires may lose about 17.8 percent of their life potential due to underinflation. Factoring in the effects of misalignment and other issues, it is estimated that over a quarter of a tire's life may be lost due to uneven wear on tire tread amounting to approximately $37 in lost tread life per tire for over 300 million tires sold just in the United States. This adds up to over 11 billion dollars lost per year due to uneven wear on tire tread.
Despite the high cost of new tires, studies have shown that tires are not well maintained. The tire manufacturer trade association known as the Rubber Manufacturers Association (RMA) estimates that only 17 percent of people may be considered “Tire Smart” (i.e., understand basics of maintaining tires). Moreover, ten percent of U.S. motorists may drive on at least one bald tire with 50 percent of passenger vehicles estimated to be misaligned, and more than 50 percent of vehicles may be underinflated.
Overworn tires also may contribute to accidents. A study performed by the National Highway Traffic Safety Administration determined that tire-related crashes were more likely as tire tread wears. For example, the accident rate of a car was estimated at 2.4 percent with full tread depth compared to an accident rate of 26 percent when the tread is worn down (e.g., 0- 2/32 inch depth). Underinflated tires may also be a risk. Tires underinflated by 25 percent may more than triple the occurrence of an accident.
Tread of tires is characterized by a surface with grooves and tread blocks. The tread blocks are designed to wear down over time, and thus the depths of the grooves may be an indicator of the nature of wear. The span and depth of a tire groove may relate to tracking the motion causing wear. Many tire related problems are assessed by a tire professional examining a latitudinal swath (i.e., cross-section) of a tire. The tread depth gauge is the lifeblood of a tire professional. For example, fleet managers use the tread depth gauge to capture ongoing (e.g., weekly, monthly) measurements of tread wear for trend analysis, diagnosis of surface wear, and/or the like. Tire dealers also use tread depth gauges when evaluating tires for replacement and/or servicing. Using a tread depth gauge to monitor tire wear, however, is error prone and may be difficult to read. Additionally, this measurement process may be dirty and place a user into contact with hazardous materials such as carbon black, a known carcinogen.
Tire impression forensics is the science of matching tire tracks to tire type. However, current practice is limited to the use of websites and a guide. For example, the Tire Industry Association (TIA) and the Technology & Maintenance Council (TMC) offer diagnostic guides that include characterizations of myriad different tire problems. Each tire problem includes a textual description of the issue with a sample photo, along with a recommended course of action. No tool currently exists in the marketplace, however, that provides the ability to electronically match worn tire tread track to tires and/or provide automatic tread identification.
Treadwear related diagnostics may be especially complicated to diagnose as tire tread may degrade in a three-dimensional (3D) pattern. Complicating the diagnostic issues, wear patterns may appear similar to one another, especially in early stages of wear. As such, a need exists for a system and method that provides an automated technique for three-dimensional analysis of tread wear.